Henry Browne was busy being a well-behaved teenager. Until the day he knocked on the door of his new, elderly neighbour and mysterious forces changed his life

He was such a nice boy. Everyone in his family agreed. An only son, of course. There's no-one more devoted than an only child… although it helps that there are no brothers or sisters to fight with. Not that Henry would ever have fought with anyone. Every evening he helped wash the dishes without being asked. He walked the dog without complaining. Other parents might sit worrying about drugs and cigarettes and nightclubs full of predatory girls. But Henry Browne seemed untouched by the modern world. He was impervious to it.

He lived in Finchley, north London… a large, Victorian house on Elmsworth Avenue, N3, which had once been rather grand but which, like many of the houses around it, had been converted into flats. The Browne family had the bottom floor with a bright and airy basement and a garden. Henry's father was the local manager of a building